A heating device using induction heating (eddy current) is proposed as a device that heats water (for example, see PTD 1). The eddy current heating device described in PTD 1 includes a rotatable rotor having permanent magnets disposed on the outer periphery thereof and a heating part made of a conductive material that is fixed to the outside of the rotor and has a flow passage inside thereof for circulating water. When the rotor rotates, magnetic field lines (magnetic flux) generated by the permanent magnets on the outer periphery of the rotor move through the heating part to produce eddy current in the heating part and heat the heating part. As a result, heat produced in the heating part is transmitted to the water circulating through the interior flow passage to heat the water.
The main object of the above technology is to supply hot water using energy such as wind power. Power generation systems have recently been proposed, which convert heat of a heating medium heated by an induction heating device into electric energy (see, for example, PTDs 2, 3). PTDs 2, 3 disclose an induction heating device including a rotor, a magnetic flux generating part provided on the outer periphery of the rotor to generate magnetic flux in the radial direction of the rotor, a tubular heating part disposed on the outside of the rotor at a distance from the rotor, and a flow passage (piping) provided in the heating part to allow a heating medium to circulate. PTDs 2, 3 illustrate a configuration having a plurality of flow passages along the axial direction of the heating part, in which a heating medium is supplied from one end side of the flow passages and discharged from the other side.